I was able to reproduce this on my system. First this is the error that happens when installing. This is what crashes Nala because of the formatter.
``` Traceback (most recent call last): File "/usr/bin/debreate", line 230, in <module> main() File "/usr/bin/debreate", line 27, in main import globals.paths File "/usr/share/debreate/globals/paths.py", line 16, in <module> import libdbr.paths File "/usr/share/debreate/lib/libdbr/paths.py", line 18, in <module> from . import sysinfo File "/usr/share/debreate/lib/libdbr/sysinfo.py", line 37, in <module> if not __os_name: ^^^^^^^^^ NameError: name '__os_name' is not defined ``` This portion happens with apt as well, although apt doesn't crash. If you use --raw-dpkg switch with Nala it will complete. I have already fixed this crash upstream but haven't released yet. I would say you should likely report this to the debreate devs, even getting the install to complete with apt, the same error is thrown when I try to run the program.